dmaengine: ioat: remove unused declarations in dma.h

ioat_ring_alloc_order and ioat_ring_max_alloc_order have
been removed since commit cd60cd96 ("dmaengine: IOATDMA:
Removing descriptor ring reshape"), so remove them.
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20220911091817.3214271-1-cuigaosheng1@huawei.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/ioat/dma.h

@@ -196,10 +196,8 @@ extern const struct sysfs_ops ioat_sysfs_ops;
 extern struct ioat_sysfs_entry ioat_version_attr;
 extern struct ioat_sysfs_entry ioat_cap_attr;
 extern int ioat_pending_level;
-extern int ioat_ring_alloc_order;
 extern struct kobj_type ioat_ktype;
 extern struct kmem_cache *ioat_cache;
-extern int ioat_ring_max_alloc_order;
 extern struct kmem_cache *ioat_sed_cache;
 
 static inline struct ioatdma_chan *to_ioat_chan(struct dma_chan *c)